Horseshoe-calk.



Patented June 1,1909.

J. PLHO ESGH. HOBSESHOE GALK.

' UNITE V oHN r. norrnson, oronroneo, ILLINOIS.

?Fiji I-IORSESI-IOE-CALK.

To all 'whom it may concern:

Beit known that I, JO N P. Horrnscn, a citizen of the United States, and aresident of the city of Chicago, Cook county, Illinois, have ,invented certain new and useful Improvements inHorseshoe-Calks; and I do hereby:- declare thatuthe following is a full, clear, and exact description of the same, reference being had to the, accompanying drawings, and ,to the lettersof reference thereon, which form a partof this specification.

Many attempts have beenmade in the past to provide a 'horse ,shoe calk adapted to be more or less self-sharpening through use and practically all such atternpts have, proven failures in practices ,for r the reason that though a calkmay'be properly shaped when the horse isfirst shodpavery short period of use, especially on stony `roads or asphalt paved streets, results inthe call: becoming rounded transversely [the shoe and also ,rounded longitudinally the ;shoe to an extent that precludesanyefcient use in obtaining a hold upon the surface. In' practice, it has been found that'this defect, due to the wear of wha'tsoever materialgthe calk may be constructed, becomesmore eXcessive as the wear is continued and frequently a very few hours of use is suiiicient to so destroy the efficiency of the calk' as to render it positively dangerous to continue the use of the horse without reshoeing or sharpening the calks. Of course, where ,the roadway is paved or is stony, such frequent reshoeing or resharpening becomessuchan eXcessive and burdensome eXpense as tObB very objectionable and horses are ,often injured because of delay or neglect of the driver to `remedy the trouble.

In a few instances, attempts have been made to provide removable calks on shoes to permit the calks to be removed for sharpening, and in some instances, conical pins have been threaded orotherwise engaged in the shoe to serveas calks, and in some instances, the solid centers of these have been of harder material than 'the outer portions, that the greater wear on the outer partmay serve in part to keep the calks sharpened or pointed. This rarely,if ever, however, serves the purpose and such calks merely become blunted or rounded inform in a manner to preclude effective service, especially where used in asphalt paved streets, which may be wet or covered witha very thin layer of ice.

The Object of this invention is to provide in fact self sharpening calks for the purpose V Specification of Letters Patent.

P j Application fied March 27, 1908. Seral No. 423,775.

plied.

Patented June 1, 1909.

specified, adapted to be either removably or permanently-secured to the shoe and adapted through wear and use to maintain a sharp edge or angle aifording a maXimum length of cutting or bearing edge upon the roadway.

It is also an Object of the invention to afford a tapered calk having an exceedingly hard outer shell to resist wear and a Central backing of eXceedingly soft iron and which is adapted to be worn away more rapidly then the outer shell, thus insuring a peripheral cutting edge and an inner cavity providing in 'effect, a cup shaped call capable of affording a broad bearing upon the street sui-face and one that never under any circumstances can become rounded and useless through wear.

The invention is shown embodied in connection with an ordinary shoe, though obviously adaptable for use in connection with 'shoes of any kind or description adapted for animal use.

The invention consists in the matters hereinafter described and more fully pointed out and defined in the appended claims.

In the drawings: Figure 1 is a bottom plan view of an ordinary horse shoe provided with toe and heel calks embodying my invention. Fig. 2 is a section taken on line 2 2 of Fig. 1. Fig 3 is an enlarged sectional detail taken through the central toe calk.

As shown in the drawings: the shoe A, which, as shown is a simple plate, but which may, of course, be of any type or character, is provided with a plurality of toe calks B, and with two heel calks B', embodying my invention, though, of course, the number and arrangement of the calks will vary, depending upon the type of shoe to which ap- Said calks, as shown, are constructed substantially as follows: A bar or rod of Swede iron or other suitable soft and tough iron or metal is cut into short sections or pieces and shaped to afford the cylindric body portion b, of the calk and the smaller cylindric neck or stem portion b', and welded around the body portion b, of the calk is a tapered ring b of high carbon steel capable of taking a very high temper to afford eX- treme hardness. This outer shell 27 of steel tapers downwardly in the form substantially of the frustum of a cone, 'and the body portion b of Swede iron or other soft metal, is drilled or otherwise provided with an aXial aperture or recess therein, as shown in Figs. 2 and 3, eXtending inwardly nearly to the stem b', and at the outer end said soft body portion at the mouth of said recess is countersunk to cut the metal away nearly to the hard outer shell 6 The shoe is provided with cylindric apertures therethrough positioned to correspond with the desired position of the calk and of a size to receive the stem b therethrough and said apertures are countersunk on opposite sides to permit the call; to fit close against the under face of the shoe, as shown in Figs. 2 and 3, on one side and to permit the riveting of the stem down on the upper side, to firmly engage the same in place.

The operation is as follows: The exceedingly hard outer shell or ring of steel which, as before stated, is tapered dcwnwardly to permit of ready disengagement from between crevices in the pavenent or elsewhere, in which the call: may be engaged, affords a comparatively thin edge for engagement with the street surface. The hardness of this outer ring or shell is such, that were it not for the soft iron backing behind the same, the call: would soon become shattered or broken through use. Said soft iron backing, however, greatly strengthens the same and the entire center of the body portion of the calk being cut away, the rounding over of the calk through use either longitudinally or transversely of the shoe is, of course, impossible. Furthermore, owing to the fact that the inner portion or backing portion of the calk is of exceedingly soft and tough iron, this wears very rapidly as compared with the harder outer steel surface, and in consequence a cavity or cup shaped contour is always afforded for the calk which insures the maximum holding efiiciency.

Of course, it is not essential that the calks be riveted in place. They may be attached to the shoe either permanently, removably or in any desired manner, and may be attached as well to a shoe of one type as to another. In any event, however, the use of such calks preeludes the necessity of frequent sharpening and owing to the pecnliar construction of the calk, permits of use of the shoe until the calhs are entirely worn away.

\V hile I have described the calks as shaped, roughly speaking, in the form of a frustum of a cone, it is evident, of course, that the shape of said calks in horizontal section may vary through a very wide range and the particular contour of the call: is inmaterial, so long as the same affords a hard outer shell and a soft tough backing material either with or without a cavity at the center of the call: Opening through the bottom of the same. I therefore do not purpose limiting this application for patent otherwise than necessitated by the prior art.

I claim as my invention:

1. A shoe calk comprising a central, soft, tough, metallic core adapted for attachment to a shoe tapered at its lower end downwardly and outwardly to a thin edge, and an encircling ring of much harder metal welded thereto and tapering downwardly and inwardly.

2. A shoe calk embracing a ring of hard metal rounded inwardly on its outer side, an inner core of soft, tough metal to which the former is welded and forming a backing therefor and having the central portion from the bottom removed to afford a cavity and the inner side of the backing thinned at the bottom within the rounded part of the hard ring, and an integral stem on said soft core adapted to afford attachment with a shoe by riveting or the like.

3. A shoe call: afording an annular bearing surface for the road or street and embracing an outer hard shell and an inner soft, tough core, said hard shell and core thinned at their lower ends and one curved inwardly and the other inclined outwardly.

4. A self sharpening shoe calk embracing a soft, tough core adapted to afford attachment with a shoe, a ring of steel welded thereto and tempered and tapering downwardly, the central portion of said soft core being cut away to afiord a downwardly Opening aperture, said ring and a portion of the core affording a broad bearing on the under side the shoe, and an integral stem on the core adapted to extend through an aperture in the shoe to afford attachment therewith by riveting.

5. An annular shoe calk affording an annular bearing surface for the street or road and embracing an exceedingly hard outer portion and a soft, tough inner portion to which the former is welded, said softer portion being countersunk in the end to afford a cup shaped interior and the core and hard outer portion being mutually thinned and inclined to afford a lower sharp edge which is self-sharpening.

In testimony whereof I have hereunto subscribed my name in the presence of two subscribing witnesses.

JOHN P. HOPPESOH. \Vitnesses K. E. HANNAH, J. U. ANGELL. 

